Drainage structure and siphoning drainage system

ABSTRACT

A drainage structure has: a bathtub (first wet area fixture) at which waste water becomes collect-and-flow waste water that is drained after having been collected; a wash place (second wet area fixture) at which waste water becomes continuous waste water that is not collected; a first drainage trap that is provided at a drain of the bathtub; a second drainage trap that is provided at the wash place; a first bypass pipe that connects a drainage pipe (downstream side region) of the first drainage trap and a drainage pipe (downstream side region) of the second drainage trap, at least a portion of the first bypass pipe being positioned higher than both the first drainage trap and the second drainage trap; a first siphoning drainage pipe that is connected to a downstream side of the first drainage trap and to a downstream side of the first bypass pipe; and a second siphoning drainage pipe that is connected to a downstream side of the second drainage trap and to a downstream side of the first bypass pipe.

TECHNICAL FIELD

The present disclosure relates to a drainage structure and a siphoning drainage system.

BACKGROUND ART

A drainage system in which a temporary storage tank for waste water is connected between a siphoning drainage pipe and a wet area fixture, such as a bathtub or a wash place or the like, is disclosed in Japanese Patent No. 4927450. This temporary storage tank is disposed in an underfloor space that is between a slab and a floor surface. Further, the drainage pipe of the bathtub is connected to the drainage trap of the wash place, and water in the bathtub is drained through the drainage pipe of the wash place.

SUMMARY OF INVENTION Technical Problem

At the time of draining water from the bathtub, because the water in the bathtub becomes collect-and-flow waste water, a large amount of waste water flows to the drainage pipe. Because the pipe diameter of the siphoning drainage pipe is smaller than that of a conventional pitched pipe, there is the concern that, until siphoning force is generated at the siphoning drainage pipe, the waste water from the bathtub will overflow into the wash place via the waste water trap. Therefore, a temporary storage tank such as that of the above-described conventional example has been devised.

However, a height of a certain extent is needed for the temporary storage tank in order to ensure the capacity of the temporary storage tank, and an underfloor space must be secured in accordance with the height hereof. Therefore, it is difficult to lower the floor in cases in which a temporary storage tank is provided.

An object of the present disclosure is to provide a drainage structure and a siphoning drainage system that enable further lowering of a floor.

Solution to Problem

A drainage structure has: a first wet area fixture at which waste water becomes collect-and-flow waste water that is drained after having been collected; a second wet area fixture at which waste water becomes continuous waste water that is not collected; a first drainage trap that is provided at a drain of the first wet area fixture; a second drainage trap that is provided at a drain of the second wet area fixture; a first bypass pipe that connects a downstream side region of the first drainage trap and a downstream side region of the second drainage trap, at least a portion of a pipeline of the first bypass pipe being positioned higher than both the first drainage trap and the second drainage trap; a first siphoning drainage pipe that is connected to a downstream side of the first drainage trap and to a downstream side of the first bypass pipe; and a second siphoning drainage pipe that is connected to a downstream side of to a downstream side of the second drainage trap and the first bypass pipe.

A siphoning drainage system has: a drainage stack pipe that is disposed in a vertical direction of a building; and a drainage structure, wherein the first siphoning drainage pipe and the second siphoning drainage pipe respectively have a lateral pipe that causes waste water to flow in a lateral direction, and a vertical pipe that is connected to the drainage stack pipe and causes waste water from the lateral pipe to flow downward.

Advantageous Effects of Invention

In accordance with the drainage structure and the siphoning drainage system relating to the present disclosure, the drainage structure and the siphoning drainage system that enables further lowering of a floor can be provided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view showing an overview of a siphoning drainage system relating to a first embodiment.

FIG. 2 is a perspective view showing a drainage structure relating to the first embodiment.

FIG. 3 is a cross-sectional view showing an initial step at a time of draining water from a bathtub, in the drainage structure relating to the first embodiment.

FIG. 4 is a cross-sectional view showing a state of draining after siphoning force is generated.

FIG. 5 is a cross-sectional view showing a state of draining from a wash place, in the drainage structure relating to the first embodiment.

FIG. 6 is an exploded perspective view showing a structure in which an apron of the bathtub is detachable, in the drainage structure of the first embodiment.

FIG. 7 is a perspective view schematically showing a drainage structure relating to a second embodiment.

FIG. 8 is a perspective view schematically showing a drainage structure relating to a third embodiment.

FIG. 9 is a perspective view schematically showing a drainage structure relating to a fourth embodiment.

FIG. 10 is a perspective view schematically showing a drainage structure relating to reference example 1.

FIG. 11 is a perspective view schematically showing a drainage structure relating to reference example 2.

FIG. 12 is a cross-sectional view showing a drainage structure relating to a fifth embodiment.

FIG. 13 is a cross-sectional view showing a drainage structure relating to a sixth embodiment.

DESCRIPTION OF EMBODIMENTS

Forms for embodying the present invention are described hereinafter on the basis of the drawings.

First Embodiment

In FIG. 1, a siphoning drainage system 10 relating to the present embodiment has a drainage stack pipe 14 and a drainage structure 16.

The drainage stack pipe 14 passes-through a through-hole 25 of a floor slab 24 of a building 15. A drainage coupling 28 that connects vertical pipes 31B, 32B that are described later is provided at the drainage stack pipe 14. Waste water from the upper portion of the drainage stack pipe 14, and waste water from a wet area fixture such as a bathtub 11 or a wash place 12 or the like that are described later, are merged. Note that, in FIG. 1, the structures of the connecting portions of the respective pipes, such as pipe couplings and the like, are omitted as appropriate.

(Drainage Structure)

The drainage structure 16 has the bathtub 11 that is an example of a first wet area fixture, the wash place 12 that is an example of a second wet area fixture, a first drainage trap 21, a second drainage trap 22, a first bypass pipe 18, a first siphoning drainage pipe 31, and a second siphoning drainage pipe 32.

The bathtub 11 is an example of a wet area fixture in which water 20 is collected and used, and the waste water therefrom is collect-and-flow waste water that is drained after having been collected. The wash place 12 is an example of a wet area fixture, and the waste water therefrom is continuous waste water that is not collected. The bathtub 11 and the wash place 12 are adjacent to one another with a gap S therebetween. The bathtub 11 and the wash place 12 may be integral with one another as illustrated, or may be separate from one another.

The first drainage trap 21 and the second drainage trap 22 are so-called water sealed traps for preventing backflow of foul odors and gasses and the like. The first drainage trap 21 is provided at a drain 41 of the bathtub 11. The second drainage trap 22 is provided at a drain 42 of the wash place 12.

The first bypass pipe 18 is a pipe that connects a drainage pipe 51, which is an example of a downstream side region of the first drainage trap 21, and a drainage pipe 52, which is an example of a downstream side region of the second drainage trap 22. The first bypass pipe 18 is provided in the gap S between the bathtub 11 and the wash place 12 so as to not be seen by users at times of regular use. Space can be utilized effectively by providing the first bypass pipe 18 in the gap S. Note that the first bypass pipe 18 may be provided at another region, such as between the bathing room and a wall of the building, or the like (not illustrated).

At least a portion of the pipeline at the first bypass pipe 18, e.g., an uppermost portion 18H, is positioned higher than both the first drainage trap 21 and the second drainage trap 22. Here, “higher than both the first drainage trap 21 and the second drainage trap 22” means higher than a top surface 21A of the first drainage trap 21 and higher than a top surface 22A of the second drainage trap 22. The first bypass pipe 18 is formed in an upside-down U-shape for example, and has a vertical pipe portion 18A that is at the first drainage trap 21 side, a vertical pipe portion 18B that is at the second drainage trap 22 side, and a connecting portion 18D of the vertical pipe portions 18A, 18B. The connecting portion 18D extends in the horizontal direction for example. The uppermost portion 18H is the bottom surface of this pipeline, and this bottom surface is positioned higher than both the first drainage trap 21 and the second drainage trap 22. In a case in which the height of the bottom surface of the pipeline at the connecting portion 18D is not uniform, the highest position thereof is the uppermost portion 18H. Note that, although the uppermost portion 18H is given as an example of the at least a portion of the pipeline of the first bypass pipe 18, a region other than the uppermost portion 18H may be positioned higher than both the first drainage trap 21 and the second drainage trap 22.

The drainage pipe 51 has an upper lateral pipe portion 51A that extends in a lateral direction from the first drainage trap 21 and merges with the vertical pipe portion 18A of the first bypass pipe 18, a vertical pipe portion 51B that extends downward from the lower end of the vertical pipe portion 18A, and a lower lateral pipe portion 51C that extends in a lateral direction from the lower end of the vertical pipe portion 51B. Similarly, the drainage pipe 52 has an upper lateral pipe portion 52A that extends in a lateral direction from the second drainage trap 22 and merges with the vertical pipe portion 18B of the first bypass pipe 18, a vertical pipe portion 52B that extends downward from the lower end of the vertical pipe portion 18B, and a lower lateral pipe portion 52C that extends in a lateral direction from the lower end of the vertical pipe portion 52B. Note that the structures of the drainage pipes 51, 52 are not limited to this, and it suffices for them to be structures that enable drainage from the first drainage trap 21 and the second drainage trap 22, respectively.

An intake valve 30 is provided at the first bypass pipe 18. The intake valve 30 is a part for causing air from the exterior to pass into the first bypass pipe 18, and waste water and causing air not to pass from the first bypass pipe 18 to the exterior. The intake valve 30 is, for example, provided at the upper end of an extension portion 18C of the vertical pipe portion 18A. When this extension portion 18C is included, it can be said that the first bypass pipe 18 is formed in a mirror-written shape in which the letter h is reversed. When the first bypass pipe 18 is viewed from the opposite side, it is shaped as the letter h. Note that the intake valve 30 may be provided at a connecting portion 18D at the first bypass pipe 18. Further, the extension portion 18C and the intake valve 30 may be provided above the vertical pipe portion 18B.

It is preferable that the height position of the uppermost portion 18H of the pipeline at the first bypass pipe 18 is equivalent to or higher than the height position of a standard water head H of the water 20 collected in the bathtub 11. The reference for the water head H is, for example, the bottom of the bathtub 11. The standard water head H corresponds to the amount of hot water that is collected within the bathtub 11 at the time when a person takes a bath, and, for example, corresponds to an amount of hot water of an extent that does not overflow from the bathtub 11 at the time when a person sits down in the bathtub 11. The uppermost position 18H is the maximum height at which overflowing does not occur between the vertical pipe portions 18A, 18B at the first bypass pipe 18, and corresponds to the height of the bottom surface of the connecting portion 18D.

In FIG. 2, the first siphoning drainage pipe 31 is connected to the a downstream side of the first drainage trap 21 and to a downstream side of the first bypass pipe 18. Further, the second siphoning drainage pipe 32 is connected to a downstream side of the second drainage trap 22 and to a downstream side of the first bypass pipe 18.

Concretely, in FIG. 1, the first siphoning drainage pipe 31 is connected to the final end of the lower lateral pipe portion 51C of the drainage pipe 51. Further, the first siphoning drainage pipe 31 has a horizontal pipe 31A that causes waste water to flow in a lateral direction, and the vertical pipe 31B that is connected to the drainage stack pipe 14 and causes waste water from the horizontal pipe 31A to flow downward. Further, the second siphoning drainage pipe 32 has a horizontal pipe 32A that causes waste water to flow in a lateral direction, and the vertical pipe 32B that is connected to the drainage stack pipe 14 and causes waste water from the horizontal pipe 32A to flow downward. The lower ends of the vertical pipes 31B, 32B are connected to the drainage coupling 28. Note that, in FIG. 1, the first siphoning drainage pipe 31 is disposed parallel to and at the rear side of the second siphoning drainage pipe 32.

As shown in FIG. 6, at the drainage structure 16, an apron 40 that structures the side surface at the bathtub 11 side of the wash place 12 may be structured so as to be removable. In this case, by removing the apron 40, maintenance of the drainage structure 16 can be carried out easily.

(Operation)

The present embodiment is structured as described above, and operation thereof is described hereinafter. In FIG. 3, in the drainage structure 16 relating to the present embodiment, waste water from the bathtub 11 becomes collect-and-flow waste water which is drained after having been collected. Therefore, a large amount of waste water is drained all at once, as compared with waste water from the wash place 12. The waste water from the bathtub 11 passes-through the first drainage trap 21, and, via the upper lateral pipe portion 51A, the vertical pipe portion 51B and the lower lateral pipe portion 51C of the drainage pipe 51, flows to the first siphoning drainage pipe 31 (the arrow A direction). Excess waste water flows into the first bypass pipe 18 (the arrow B direction) until siphoning force is generated at the first siphoning drainage pipe 31. Accompanying the flowing-in of waste water, the air within the first bypass pipe 18 is pushed-out toward the second drainage trap 22 side (the arrow C direction).

The first bypass pipe 18 is formed in an upside-down U-shape, and the uppermost portion 18H of the pipeline is positioned higher than both the first drainage trap 21 and the second drainage trap 22. Therefore, it is difficult for the waste water that has flowed into the first bypass pipe 18 to flow toward the second drainage trap 22 side. In particular, in a case in which the height position of the uppermost portion 18H of the pipeline at the first bypass pipe 18 is equivalent to the height position of the standard water head H of the water that has collected in the bathtub 11, it is difficult for overflowing from the vertical pipe portion 18A to the vertical pipe portion 18B to occur. Note that overflowing of an extent such that the water sealing of the second drainage trap 22 does not break is permissible.

In FIG. 4, when siphoning force arises at the first siphoning drainage pipe 31, the waste water from the bathtub 11 and the waste water that has flowed-into the first bypass pipe 18 are, via the first siphoning drainage pipe 31, rapidly discharged (the arrow A direction), and the water level of the bathtub 11 drops (the arrow D direction). At this time, because outside air is taken-into the first bypass pipe 18 from the intake valve 30 (the arrow E direction), negative pressure being applied to the second drainage trap 22 side is suppressed. Therefore, the water sealing of the second drainage trap 22 does not break.

In this way, in accordance with the drainage structure 16, collect-and-flow waste water from the bathtub 11 overflowing into the wash place 12 can be suppressed even if a temporary storage tank such as a conventional temporary storage tank is not used.

On the other hand, in FIG. 5, the waste water from the wash place 12 is continuous waste water that has not been collected. The waste water from the wash place 12 passes-through the second drainage trap 22, and, via the upper lateral pipe portion 52A, the vertical pipe portion 52B and the lower lateral pipe portion 52C of the drainage pipe 52, flows to the second siphoning drainage pipe 32 (the arrow F direction). The air within the pipeline at the first bypass pipe 18 is pushed-out via the first bypass pipe 18 toward the first drainage trap 21 side (the arrow G direction), and therefore, drainage from the wash place 12 is carried out smoothly. Because there is hardly any water head in the case of continuous waste water, waste water does not flow into the vertical pipe portion 18B of the first bypass pipe 18. When siphoning force arises at the second siphoning drainage pipe 32, the waste water from the wash place 12 is discharged rapidly via the second siphoning drainage pipe 32 (the arrow A direction). At this time, if there is waste water from only the wash place 12, there is hardly any generation of negative pressure at the first bypass pipe 19. However, in a case in which negative pressure arises at the first bypass pipe 18 such as at the time of simultaneous draining of the wash place 12 and the bathtub 11 or the like, external air is taken-in through the intake valve 30, and therefore, the water sealing of the first drainage trap 21 and the second drainage trap 22 does not break.

In FIG. 1, in the siphoning drainage system 10 relating to the present embodiment, waste water from the bathtub 11 can be made to flow to the drainage stack pipe 14 through the horizontal pipe 31A and the vertical pipe 31B that the first siphoning drainage pipe 31 has. Further, in this siphoning drainage system 10, waste water from the wash place 12 can be made to flow to the drainage stack pipe 14 through the horizontal pipe 32A and the vertical pipe 32B that the second siphoning drainage pipe 32 has.

In this way, in accordance with the drainage structure 16 and the siphoning drainage system 10 relating to the present embodiment, because there is no need for a temporary storage tank as a conventional temporary storage tank, further lowering of the floor at the set place of the bathtub 11 or the like, at which collecting, flowing and draining are carried out, is possible.

Second Embodiment

In FIG. 7, a drainage structure 26 relating to the present embodiment has auxiliary chambers 71, 72 at at least one of, e.g., at both of, a downstream side region of the first drainage trap 21 and a downstream side region of the second drainage trap 22. The auxiliary chamber 71 is provided at a downstream side region of the first drainage trap 21. The auxiliary chamber 72 is provided at a downstream side region of the second drainage trap 22.

The auxiliary chambers 71, 72 are large diameter portions (enlarged inner diameter portions) that are provided at, for example, the drainage pipes 51, 52 respectively. The height dimensions of the auxiliary chambers 71, 72 are set to be lower than that of a conventional temporary storage tank, and are made to be sizes such that the auxiliary chambers 71, 72 can be disposed within the space needed for placement of the first drainage trap 21, the second drainage trap 22 and the drainage pipes 51, 52. Accordingly, there is no need to make the underfloor space superfluously large in order to set the auxiliary chambers 71, 72.

In this illustrated example, the auxiliary chambers 71, 72 are both disposed at the upstream side of the first bypass pipe 18. However, either one or both of the auxiliary chambers 71, 72 may be disposed at the downstream side of the first bypass pipe 18.

In this drainage structure 26, excess waste water that has exceeded the capacity of the first bypass pipe 18 can be received by the auxiliary chambers 71, 72. In cases of using water, which has been drawn-up from the bathtub 11 (FIG. 1), in the wash place 12 (FIG. 1), a larger amount of water than at usual times is drained from the wash place 12. In such cases as well, due to the waste water being received by the auxiliary chambers 71, 72, waste water from the wash place 12 stagnating can be suppressed. Further, it is possible to handle an even larger amount of collect-and-flow waste water from the bathtub 11.

Because other portions are similar to the first embodiment, the same portions are denoted by the same reference numerals in the drawings, and description thereof is omitted.

Third Embodiment

In FIG. 8, in a drainage structure 36 relating to the present embodiment, a vent pipe 74 that is a substitute for the intake valve 30 (see FIG. 2) is connected to the first bypass pipe 18. The vent pipe 74 extends to, for example, the exterior of the building, and a final end 74A thereof is open to the atmosphere.

In this drainage structure 36, because the vent pipe 74 is provided instead of the intake valve 30 (FIG. 2), space for placement of the intake valve 30 is not needed.

At the time when siphoning force is generated at the first siphoning drainage pipe 31, because outside air is taken into the first bypass pipe 18 from the vent pipe 74, the water sealing of the second drainage trap 22 does not break. Also at times when siphoning force is generated at the second siphoning drainage pipe 32, because outside air is taken into the first bypass pipe 18 from the vent pipe 74, the water sealing of the first drainage trap 21 does not break.

Because other portions are similar to the first embodiment, the same portions are denoted by the same reference numerals in the drawings, and description thereof is omitted.

Fourth Embodiment

In FIG. 9, a drainage structure 46 relating to the present embodiment has the third drainage trap 83 and the fourth drainage trap 84, siphoning drainage pipes 93, 94, individual vent pipes 103, 104, a header 80, and a merging vent pipe 90.

The third drainage trap 83 is provided for the drain (not shown) of a washing machine that is an example of another wet area fixture. The fourth drainage trap 84 is provided for a washstand that is an example of another wet area fixture. The third drainage trap 83 and the fourth drainage trap 84 are so-called water sealed traps for preventing backflow of foul odors and gasses and the like.

A drainage pipe 113 is connected to the downstream side of the third drainage trap 83. The siphoning drainage pipe 93 is connected to the downstream side of the drainage pipe 113. Further, a drainage pipe 114 is connected to the downstream side of the fourth drainage trap 84. The siphoning drainage pipe 94 is connected to the downstream side of the drainage pipe 114.

One end of the individual air vent pipe 103 is connected to a downstream side region (the drainage pipe 113) of the third drainage trap 83. Further, one end of the individual vent pipe 104 is connected to a downstream side region (the drainage pipe 114) of the fourth drainage trap 84. The other ends of the individual vent pipes 103, 104 are respectively connected to the header 80.

The header 80 is a pipe coupling to which the vent pipe 74 and the individual vent pipes 103, 104 are connected. The merging vent pipe 90 is connected to the header, and is open to the atmosphere. Concretely, the merging vent pipe 90 extends to the exterior of the building for example, and a final end 90A thereof opens to the atmosphere.

In this drainage structure 46, because the vent pipe 74 and the individual vent pipes 103, 104 are provided instead of the intake valve 30 (see FIG. 2), space for placement of the intake valve 30 is not needed. Further, there is a structure in which the vent pipe 74 and the individual vent pipes 103, 104 are collected together at the header 80 and open to the atmosphere via the merging vent pipe 90. Accordingly, there is no need to respectively extend the vent pipe 74 and the individual vent pipes 103, 104 to the exterior. Due thereto, intake and exhaust can be carried out collectively, and the number of parts can be reduced as compared with a case in which the vent pipe 74 and the individual vent pipes 103, 104 are disposed so as to individually open to the atmosphere.

Because other portions are similar to the first embodiment, the same portions are denoted by the same reference numerals in the drawings, and description thereof is omitted.

Reference Example 1

In FIG. 10, in a drainage structure 56 relating to the present reference example, the first siphoning drainage pipe 31 is connected to the downstream side of the drainage pipe 51 that extends from the first drainage trap 21. Further, the second siphoning drainage pipe 32 is connected to the downstream side of the drainage pipe 52 that extends from the second drainage trap 22. Namely, the drainage path from the first drainage trap 21 and the drainage page from the second drainage trap 22 are independent of one another.

Accordingly, even if collecting, flowing and draining from the first drainage trap 21 are carried out, that waste water does not flow into the second drainage trap 22 side. Therefore, the collect-and-flow waste water from the bathtub 11 overflowing into the wash place 12 can be suppressed (FIG. 1).

Because other portions are similar to the first embodiment, the same portions are denoted by the same reference numerals in the drawings, and description thereof is omitted.

Reference Example 2

In FIG. 11, in a drainage structure 66 relating to the present reference example, intake valves 111, 112, are further provided in reference example 1. A branch pipe 121 that extends upward is connected to the drainage pipe 51. The intake valve 111 is provided at the upper end of this branch pipe 121. Further, a branch pipe 122 that extends upward is connected to the drainage pipe 52. The intake valve 112 is provided at the upper end of this branch pipe 122. The structures of the intake valves 111, 112 are similar to that of the intake valve 30 of the first embodiment.

In the present reference example, in the same way as in reference example 1, even if collecting, flowing and draining from the first drainage trap 21 are carried out, that waste water does not flow into the second drainage trap 22 side. Therefore, the collect-and-flow waste water from the bathtub 11 overflowing into the wash place 12 can be suppressed (FIG. 1).

Because the intake valve 111 is added to the drainage pipe 51, outside air is taken-in from the intake valve 111 at the time of draining water from the first drainage trap 21. Further, because the intake valve 112 is added to the drainage pipe 52, outside air is taken-in from the intake valve 112 at the time of draining water from the second drainage trap 22. Accordingly, waste water from the first drainage trap 21 and waste water from the second drainage trap 22 both flow easily.

Because other portions are similar to the first embodiment and reference example 1, the same portions are denoted by the same reference numerals in the drawings, and description thereof is omitted.

Fifth Embodiment

In FIG. 12, a drainage structure 76 relating to the present embodiment has a second bypass pipe 218. This second bypass pipe 218 connects the second drainage trap 22 side and the first drainage trap 21 side at the first bypass pipe 18, at a position that is lower than the uppermost portion of the first bypass pipe 18. The bottom surface of the pipeline at the second bypass pipe 218 is disposed lower than a top surface 22H of the second drainage trap 22. Further, the bottom surface of the pipeline at the second bypass pipe 218 is disposed higher than a bottom surface 52D at the upper lateral pipe portion 52A of the drainage pipe 52.

The second bypass pipe 218 extends in a lateral direction for example. Note that the second bypass pipe 218 may be inclined with respect to the horizontal direction, or may be curved. In this way, in a case in which the height of the bottom surface of the pipeline at the second bypass pipe 218 is not uniform, the highest position of the bottom surface is disposed lower than the top surface 22H of the second drainage trap 22 and higher than the bottom surface 52D of the upper lateral pipe portion 52A.

A first check valve 19 is provided at, for example, the connecting portion 18D at the first bypass pipe 18. The first check valve 19 is structured so as to permit flow from the second drainage trap 22 side to the first drainage trap 21 side and so as to not permit flow toward the opposite side. Note that the position of the first check valve 19 is not limited to the connecting portion 18D, and may be provided at the vertical pipe portion 18B for example. Further, the first check valve 19 may be structured so as to permit, to a certain extent, flow from the first drainage trap 21 side to the second drainage trap 22 side.

A second check valve 219 is provided at the second bypass pipe 218. The second check valve 219 is structured so as to permit flow from the second drainage trap 22 side to the first drainage trap 21 side and so as to not permit flow toward the opposite side. Note that the second check valve 219 may be structured so as to permit, to a certain extent, flow from the first drainage trap 21 side to the second drainage trap 22 side.

Even in a case in which not all of the waste water from the wash place 12 enters into the second drainage trap 22 but the second drainage trap 22 becomes full of water, in accordance with the present embodiment, the excess waste water passes-through the second bypass pipe 218, and, via the vertical pipe portion 51B and the lower lateral pipe portion 51C of the drainage pipe 51, flows to the first siphoning drainage pipe 31 (FIG. 1) (the arrow H direction). In the present embodiment, the bottom surface of the pipeline at the second bypass pipe 218 is disposed higher than the bottom surface 52D of the upper lateral pipe portion 52A of the drainage pipe 52. Accordingly, the waste water from the wash place 12 does not always flow to the second bypass pipe 218, and the second siphoning drainage pipe 32 rapidly becomes filled with water, and therefore, the start of siphoning is not delayed.

Further, in the present embodiment, the bottom surface of the pipeline at the second bypass pipe 218 is disposed lower than the top surface 22H of the second drainage trap 22. Accordingly, in a case in which it seems that waste water will overflow from the second drainage trap 22, the waste water flows to the second bypass pipe 218, and therefore, the waste water overflowing from the second drainage trap 22 can be suppressed.

Moreover, because the second check valve 219 is provided at the second bypass pipe 218, flow from the first drainage trap 21 side through the second bypass pipe 218 to the second drainage trap 22 side is suppressed. Further, because the first check valve 19 is provided at the connecting portion 18D of the first bypass pipe 18, at the time of draining the bathtub 11, it is even more difficult for flow from the first drainage trap 21 side through the first bypass pipe 18 to the second drainage trap 22 side, i.e., overflowing from the vertical pipe portion 18A to the vertical pipe portion 18B, to arise.

Because other portions are similar to the first embodiment, the same portions are denoted by the same reference numerals in the drawings, and description thereof is omitted.

Sixth Embodiment

In FIG. 13, a drainage structure 86 relating to the present embodiment is structured such that the first check valve 19 of the first bypass pipe 18 in the fifth embodiment is omitted. At the first bypass pipe 18, as described in the first embodiment, by appropriately setting the height of the uppermost portion 18H, it can be made such that overflow does not occur between the vertical pipe portions 18A, 18B at the first bypass pipe 18. Accordingly, by omitting the first check valve 19 as in the present embodiment, the structure can be simplified and the cost can be reduced.

OTHER EMBODIMENTS

Although examples of embodiments of the present invention have been described above, embodiments of the present invention are not limited to the above, and, other than the above, can of course be implemented by being modified in various ways within a scope that does not depart from the gist thereof.

Although the bathtub 11 is given as an example of the first wet area fixture, the first wet area fixture may be a fixture at which waste water collects and flows, such as a washing machine or the like. Further, although the wash place 12 is given as an example of the second wet area fixture, the second wet area fixture may be a fixture at which waste water is continuous water, such as a wash stand, kitchen, dishwasher, or the like.

Although the drainage pipe 51 is given as an example of the downstream side region of the first drainage trap 21 to which the first bypass pipe 18 is connected, the downstream side region is not limited to this. Similarly, although the drainage pipe 52 is given as an example of the downstream side region of the second drainage trap 22 to which the first bypass pipe 18 is connected, the downstream side region is not limited to this. For example, the first bypass pipe 18 may be directly connected to at least one of the first drainage trap 21 and the second drainage trap 22.

Although the intake valve 30 is provided at the first bypass pipe 18, the intake valve 30 may be omitted provided that the water sealing of the first drainage trap 21 and the second drainage trap 22 does not break.

Note that the disclosure of Japanese Patent Application No. 2017-33512 filed on Feb. 24, 2017 is, in its entirety, incorporated by reference into the present specification. All publications, patent applications, and technical standards mentioned in the present specification are incorporated by reference into the present specification to the same extent as if such individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference. 

1. A drainage structure, comprising: a first wet area fixture at which waste water becomes collect-and-flow waste water that is drained after having been collected; a second wet area fixture at which waste water becomes continuous waste water that is not collected; a first drainage trap that is provided at a drain of the first wet area fixture; a second drainage trap that is provided at a drain of the second wet area fixture; a first bypass pipe that connects a downstream side region of the first drainage trap and a downstream side region of the second drainage trap, at least a portion of a pipeline of the first bypass pipe being positioned higher than both the first drainage trap and the second drainage trap; a first siphoning drainage pipe that is connected to a downstream side of the first drainage trap and to a downstream side of the first bypass pipe; and a second siphoning drainage pipe that is connected to a downstream side of the second drainage trap and to a downstream side of the first bypass pipe.
 2. The drainage structure of claim 1, wherein an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap.
 3. The drainage structure of claim 1, wherein an intake valve is provided at the first bypass pipe.
 4. The drainage structure of claim 1, wherein a vent pipe is connected to the first bypass pipe.
 5. The drainage structure of claim 4, further comprising: a third drainage trap that is provided for a third wet area fixture; a siphoning drainage pipe that is connected to a downstream side of the third drainage trap; an individual vent pipe that is connected to a downstream side region of the third drainage trap; a header to which the vent pipe and the individual vent pipe are connected; and a merging vent pipe that is connected to the header and is open to the atmosphere.
 6. The drainage structure of claim 1, comprising a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap.
 7. The drainage structure of claim 6, comprising: a drainage pipe that connects the second drainage trap and the second siphoning drainage pipe, wherein the bottom surface of the pipeline at the second bypass pipe is disposed so as to be higher than a bottom surface of the drainage pipe.
 8. The drainage structure of claim 6, wherein a first check valve, which permits flow from the second drainage trap side to the first drainage trap side and does not permit flow toward an opposite side, is provided at the first bypass pipe.
 9. The drainage structure of claim 6, wherein a second check valve, which permits flow from the second drainage trap side to the first drainage trap side and does not permit flow toward the opposite side, is provided at the second bypass pipe.
 10. A siphoning drainage system, comprising: a drainage stack pipe that is disposed in a vertical direction of a building; and the drainage structure of claim 1, wherein each of the first siphoning drainage pipe and the second siphoning drainage pipe has a lateral pipe that causes waste water to flow in a lateral direction, and has a vertical pipe that is connected to the drainage stack pipe and causes waste water from the lateral pipe to flow downward.
 11. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, and an intake valve is provided at the first bypass pipe.
 12. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, and a vent pipe is connected to the first bypass pipe.
 13. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, and the drainage structure further comprises a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap.
 14. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, an intake valve is provided at the first bypass pipe, and the drainage structure further comprises a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap.
 15. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, a vent pipe is connected to the first bypass pipe, and the drainage structure further comprises a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap.
 16. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, and the drainage structure further comprises: a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap, and a drainage pipe that connects the second drainage trap and the second siphoning drainage pipe, wherein the bottom surface of the pipeline at the second bypass pipe is disposed so as to be higher than a bottom surface of the drainage pipe.
 17. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, and the drainage structure further comprises: a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap, a drainage pipe that connects the second drainage trap and the second siphoning drainage pipe, and a first check valve, which permits flow from the second drainage trap side to the first drainage trap side and does not permit flow toward an opposite side, is provided at the first bypass pipe.
 18. The drainage structure of claim 1, wherein: an auxiliary chamber is provided at at least one of the downstream side region of the first drainage trap or the downstream side region of the second drainage trap, and the drainage structure further comprises: a second bypass pipe that, at a position that is lower than an uppermost portion of the first bypass pipe, connects a side of the first drainage trap and a side of the second drainage trap side at the first bypass pipe, the second bypass pipe having a pipeline disposed such that a bottom surface of the pipeline is lower than a top surface of the second drainage trap, and a drainage pipe that connects the second drainage trap and the second siphoning drainage pipe, wherein a second check valve, which permits flow from the second drainage trap side to the first drainage trap side and does not permit flow toward the opposite side, is provided at the second bypass pipe. 